This application relates in general to lighting systems and particularly to fluorescent lighting with dimming capabilities.
Many residential and commercial light dimming applications are fitted with triac based dimmers, also known as phase chop dimmers. These dimmers work by removing or chopping parts of the AC input voltage waveform to the lamp. These dimmers work well with ordinary incandescent light bulbs because the removal or chopping of the voltage waveform reduces the power transfer to the light bulb hence achieving dimming. However, these triac based dimmers do not work well with conventional fluorescent lamp circuits because the input waveform to a fluorescent lamp circuit is not injected directly into the filaments of a lamp as with incandescent lamps, but the waveform is injected into a fluorescent lamp circuit sometimes called a ballast circuit. The ballast circuit's response to the chopped waveform is unsatisfactory and does not achieve dimming.
Because, triac based dimmers are common both in residential and commercial applications, a fluorescent lamp dimming circuit that operates with a triac based dimmer is desirable.